Coagulation and lidding/ Delidding, brining and ripening in butter & cheese production

After pasteurisation, the milk mixture is carefully fed into a buffer tank without taking in any air, if possible, in order to avoid casein losses in the whey. Held here at approx. 30 °C, the "starter" (e.g. rennet) is added to the mixture via an automatic dosing system, with careful stirring for 2-3 minutes to coagulate (curdle) the cheese from the milk. This enables the bacteria to be evenly distributed in the liquid, and gives them time to acclimatise. This pre-ripening time is around 30 to 60 minutes. The mixture is now pumped through a sieve after a quality test. Depending on the type of cheese being produced, this breaks the solid content down into grains with a size of 3 to 15 mm. The finer the cut, the lower the moisture content of the resulting cheese. Gentle stirring keeps the grains evenly suspended in the whey to prevent clumping. The mixture is pumped from the sieve into a buffer tank, and then into the prepress, block cutting and moulding machine. After moulding, the curd is finally pressed, then placed in a salt bath for a period (a few hours to 2 days) and then stored to mature, which might take a period of a few days to several months or even years.

For the instrumentation of the process steps, KROHNE offers exactly the right devices for temperature and level measurement. For example, precise and hygienic temperature sensors can be used to control the coagulation process. FMCW radar level transmitters determine the level continuously and without contact, despite the presence of agitators, and capacitive level switches provide reliable information about the minimum and maximum liquid levels in the buffer tanks.